1978429890240 has 896 divisors, whose sum is σ = 7913993011200. Its totient is φ = 462633431040.

The previous prime is 1978429890163. The next prime is 1978429890251. The reversal of 1978429890240 is 420989248791.

1978429890240 is a `hidden beast` number, since 1 + 97 + 8 + 429 + 89 + 0 + 2 + 40 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 117037629 + ... + 117054531.

Almost surely, 2^{1978429890240} is an apocalyptic number.

1978429890240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1978429890240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3956996505600).

1978429890240 is an abundant number, since it is smaller than the sum of its proper divisors (5935563120960).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1978429890240 is a wasteful number, since it uses less digits than its factorization.

1978429890240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17002 (or 16986 counting only the distinct ones).

The product of its (nonzero) digits is 20901888, while the sum is 63.

The spelling of 1978429890240 in words is "one trillion, nine hundred seventy-eight billion, four hundred twenty-nine million, eight hundred ninety thousand, two hundred forty".